1 files changed, 16 insertions, 0 deletions
diff --git a/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp b/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
index fc15dc1e6032..4820b9f7de58 100644
--- a/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
+++ b/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp
@@ -161,6 +161,22 @@ int llvm::dlltoolDriverMain(llvm::ArrayRef<const char *> ArgsArr) {
   if (Path.empty())
     Path = getImplibPath(Def->OutputFile);
 
+  if (Machine == IMAGE_FILE_MACHINE_I386 && Args.getLastArg(OPT_k)) {
+    for (COFFShortExport& E : Def->Exports) {
+      if (E.isWeak() || (!E.Name.empty() && E.Name[0] == '?'))
+        continue;
+      E.SymbolName = E.Name;
+      // Trim off the trailing decoration. Symbols will always have a
+      // starting prefix here (either _ for cdecl/stdcall, @ for fastcall
+      // or ? for C++ functions). (Vectorcall functions also will end up having
+      // a prefix here, even if they shouldn't.)
+      E.Name = E.Name.substr(0, E.Name.find('@', 1));
+      // By making sure E.SymbolName != E.Name for decorated symbols,
+      // writeImportLibrary writes these symbols with the type
+      // IMPORT_NAME_UNDECORATE.
+    }
+  }
+
   if (writeImportLibrary(Def->OutputFile, Path, Def->Exports, Machine, true))
     return 1;
   return 0;